Vietnam's top diplomat was on his way to North Korea Tuesday amid reports that North Korean leader Kim Jong-un appears to be set for a state visit to the Southeast Asian country late this month.

Foreign Minister Pham Binh Minh, who doubles as Vietnam's deputy prime minister, left for Beijing on an Air China flight earlier in the day. He's expected to head to Pyongyang by an Air Koryo flight scheduled to take off from the Chinese capital at 12:30 a.m., a source said. He is accompanied by five government officials, including the ministry's protocol chief, according to the source.

Foreign Minister Pham Binh Minh (AP)

Earlier this week, the ministry's spokeswoman, Le Thi Thu Hang, wrote Monday on Twitter that he will travel to the North through Thursday at the invitation of his counterpart, Ri Yong-ho.

The North's leader is scheduled to meet again with US President Donald Trump in Hanoi on Feb. 27-28.

Many observers bet that Kim will pay a state visit to Vietnam just before or after his meeting with Trump, which expected to focus on fleshing out Pyongyang's additional denuclearization steps and Washington's corresponding measures.

If Kim does so, he will be the first North Korean leader to visit the country in 54 years. Kim Il-sung, the country's late founder and grandfather of the current leader, visited Hanoi in October 1964. (Yonhap)